Scans for peripherals that are advertising services.
- iOS 5.0+
- macOS 10.7+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 4.0+
- Core Bluetooth
A dictionary of options for customizing the scan. For available options, see Peripheral Scanning Options.
You can provide an array of
CBUUID objects — representing service UUIDs — in the
service parameter. When you do, the central manager returns only peripherals that advertise the services you specify. If the
service parameter is
nil, this method returns all discovered peripherals, regardless of their supported services.
If the central manager is actively scanning with one set of parameters and it receives another set to scan, the new parameters override the previous set. When the central manager discovers a peripheral, it calls the
central method of its delegate object.
Your app can scan for Bluetooth devices in the background by specifying the
bluetooth-central background mode. To do this, your app must explicitly scan for one or more services by specifying them in the
service parameter. The
CBCentral scan option has no effect while scanning in the background.